High voltage gas type circuit interrupter



Dec. 29, 1964 m ETAL 3,163,736

HIGH VOLTAGE GAS TYPE CIRCUIT INTERRUPTER Filed May 23, 1961 8 Sheets-Sheet l Dec. 29, 1964 J, J. MIKOS ETAL 3,163,736

HIGH VOLTAGE GAS TYPE CIRCUIT INTERRUPTER Filed May 23. 1961 8 Sheets-Sheet 2 Dec. 29, 1964 J. J. MIKOS ETAL HIGH VOLTAGE GAS TYPE CIRCUIT INTERRUPTER Filed May 23, 1961 8 Sheets-Sheet 3 Dec. 29, 1964 J, J. MIKOS ETAL HIGH VOLTAGE GAS TYPE CIRCUIT INTERRUPTER 8 Sheets-Sheet 4 Filed May 25, 1961 Dec. 29, 1964 J. .1. MlKOS ETAL 3,163,736

HIGH VOLTAGE GAS TYPE CIRCUIT INTERRUFTER Filed May 23, 1961 8 Sheets-Sheet 5 Dec. 29, 1964 J. J. MIKOS ETAL HIGH VOLTAGE GAS TYPE (QIRCUIT INTERRUPTER 8 Sheets-Sheet 6 Filed May 23, 1961 Dec. 29, 1964 J. J. MlKOS ETAL HIGH VOLTAGE GAS TYPE CIRCUIT INTERRUPTER 8 Sheets-Sheet 7 Filed May 23, 1961 29, 1964 J. .1. MIKOS ETAL HIGH VOLTAGE GAS TIPE CIRCUIT INTERRUPTER 8 Sheets-Sheet 8 Filed y 25. 1961 khwmww EQRQQQQN United States Patent Ofiice 3,163,736 Patented Dec. 29, 1964 3,163,736 HIGH VOLTAGE GAS TYPE (IIRCUIT INTERRUPTER John J. Mikes, Highland Park, and Leonard V. Chahala, Mag wood, lib, assiguors to S 8; C Electric (Jompany,

Chicago, EL, a corporation of Delaware Filed May 23, 1951, Ser. No. ll1fi98 33 Claims. (Cl. 206-145) This invention relates, generally, to high voltage alternating current circuit interrupters and it has particular relation to such circuit interrupters in which an are extinguishing gas is employed for assisting in the circuit interruption and prevention of restriking of the circuit. once it has been opened. It constitutes an improvement over the invention disclosed in copending application Serial No. 704,397, filed December 23, 1957 now Patent No. 3,030,- 481, issued April 17, 1962, and the disclosure thereof is incorporated herein by this reference.

Among the objects of this invention are: To provide a new and improved manner for sealing the ends of the insulating housing in which separable contacts are located in a filling of arc extinguishing gas under pressure; to employ hermetic seals for this purpose; to mount the separable contacts in a rigid structure insertable as a unit from one end of the housing; to clamp the rigid structure to one terminal and to couple it resiliently to the other terminal in order to take care of relative expansion and contraction of the parts; to bridge the contacts by a rigid insulating structure; to provide for several inches of contact travel and to employ bellows means capable of accommodating such travel for hermetically sealing the operating means for the separable contact means which extends out of the housing to an operating mechanism; to reduce the vibration of the bellows means incident to the acceleration and the stopping of the movable contact means in the open position; to employ for the separable contact means parallel connected main and auxiliary contact means; to bias the separable contact means toward open position by the pressure of the arc extinguishing gas in the housing; to provide in a new and improved manner for directing a fiow of the are extinguishing gas to the gap formed on opening of the contact means; to provide a pump for circulating the gas to assist in extinguishing the arc, the pump employing relatively slidable pump and piston cylinders with insulating piston rings therebetween; to employ series connected separable contact means shunted in their open position by high resistance conducting paths formed by coatings on insulators that make up part of the rigid structure; and to shield those insulators having the high resistance conducting coatings from the products of arcs drawn on opening of the separable contact means.

In the drawings:

FIG. 1 is a View, in side elevation, of switch means embodying the present invention, the switch means being shown in the upright position.

FIG. 2 is a view, similar to FIG. 1, but showing the switch means in a vertical position.

FIG. 3 is a top plan View, at an enlarged scale, of the switch means shown in FIG. 1.

FIG. 4 is a view, in side elevation, of the switch means shown in FIG. 3. 7

FIGS. 5A and 5B, taken together with the views being placed in end to end relation, show at an enlarged scale a vertical cross sectional view of the current interrupter which forms a part of the switch means shown in FIGS. 1-4.

FIG. 6 is a vertical sectional view taken generally along the line 6--6 of FIG. 5A.

FIG. 7 is a horizontal sectional view taken generally along the line 7-7 of FIGS. 5A-5B to show the rigid insulating bridging structure, the main separable contact means being omitted.

FIG. 8 is a vertical sectional view taken generally along the line 8-8 of FIG. 513.

FIG. 9 is a view taken generally along the line 99 of FIG. 5A showing partly in end elevation and partly in section the terminal at the left end of the housing for the current interrupter.

FIG. 10 is a vertical sectional view taken generally along the line 1(l-10 of FIG. 5A.

FIG. 11 is a view in side elevation and at a reduced scale of a spring plate employed at the right end of the housing shown in FIG. 5B.

FIG. 12 is a front elevation view of the spring plate shown in FIG. 11.

FIGS. 13A and 13B, taken together in end to end relation, correspond to FIGS. 5A and 5B and show series connected main and auxiliary contact means in the current interrupter.

FIG. 14 is a vertical sectional view taken generally along the line 14-14 of FIG. 13B.

FIGS. 15A and 1513, taken together in end to end relation, constitute a top plan view of the series connected contact structure within the housing of the current interrupter shown in FIGS. 13A and 133, the view being taken generally along the line 15 15 of these figures.

eferring now particularly to FIGS. l-4 of the drawings, it will be observed that the reference character 10 designates, generally, switch means in which the present invention is embodied. FIG. 1 shows the switch means 10 in a horizontal upright position while FIG. 2 shows the switch means in a vertical position. It will be understood that the switch means 10 can be located in an inverted position which would be upside down in respect to that shown in FIG. 1.

The switch means 10 includes a base, indicated generally at 11, that may be formed of a pair of rolled steel channels suitably secured together. Mounted on the base 11 are a first insulator 12, a second insulator 13 which is rotatable and a third insulator 14. The second insulator 13 is rotatably mounted on a bearing 15 that is carried by the base 11 and it has an arm 16 extending therefrom for connection to a suitable operating linkage that is indicated, generally at 17. It will be understood that, for three phase operation, three of the switch means 10 are mounted on a suitable switching structure in proper spaced relation, depending upon the voltage of the circuit, and that suitable operating means, common to the operating linkage 17 is provided for effecting the simultaneous rotation of the second insulator 13 of each switch means 10 for effecting simultaneous operation of the three switch means 10 for either opening or closing the circuit as may be required. Such an operating mechanism is illustrated and described in the copending application above referred to, now Patent No. 3,030,481, issued April 17, 1962.

Extending upwardly from and rotatable with the second insulator 13 is a shaft 18. The shaft 18 extends through and is rotatably mounted on a mechanism housing 19 the details of construction of which are set forth in the patent above referred to together with the operating mechanism therein which is controlled by the shaft i8. For present purposes it is pointed out that the shaft 18 extends through the mechanism housing 19 and carries at its upper end a switch crank 20 which is rotatable therewith. The switch crank it is pivotally connected to a link 21 that is pivoted at 22 to an arm 23 which extends from a switch blade 24 that forms a part of a disconnnecting switch that is indicated, generally, at 25. The switch blade 24 is pivoted at 26 on a bracket 27 which is carried by one The details of construction of the disconnecting switch are conventional and may be as disclosed in US. Patent No. 2,818,474, issued December 31, 1957.

It is desirable that the switch blade 24 be opened only after the circuit has been opened previously by some other nreans. The reason for this is to prevent the draw- .ing of an are between the swinging end of the switch blade 24 and the line contact member 28 when the circuit is interrupted under load which might result in damage to these parts or in the creation of a fault by arcing over to an adjacent phase or to ground. For this purpose there is mounted between the mechanism housing 13 and a line terminal 31, which is carried by the third insulator 14, a current interrupter that is indicated, generally, at 32. As will appear hereinafter, separable contact means are provided in the current interrupter 32 which are operated by the mechanism within the mechanism housing 19 under the control of the shaft 18 as described in detail in the copending application above referred to, now Patent No. 3,030,481. Since the present invention is directed principally to the construction of the current interrupter 32 the following description will pertain to its preferred arrangements, it being understood that the operating mechanism referred to is employed for controlling the operation of the current interrupter 32.

The current interrupter 32 is provided with an insulating housing 33 that preferably is a one piece hollow porcelain housing having a cylindrical interior and external corrugations to increase its flashover value between the ends. At the ends there are provided terminals that are indicated, generally, at 34 and 35 the details of construction of which and method of application will be described hereinafter.

Referring now to FIGS. 5A-5B of the drawings, since the insulator housing 33 is intended to contain a filling of arc extinguishing gas, such as Freon, sulphurhexafluoride and the like, provision is made for hermetically sealing the ends thereof. As will appear, the hermetic seals are provided in such manner that their sole purpose essentially is to act as sealing mean and they are not required to transmit any appreciable mechanical stresses incident to the operation of the current interrupter 32. Around the extreme end of each end of the insulating housing 33 there is provided an external metallic band 36, preferably formed of platinum, which facilitates soldering thereto. In addition at locations spaced slightly from the extreme ends of the insulating housing 33, there are provided sand bands 37 which facilitate the cementing of the terminals 34 and 35 thereto. In order to prevent the solder from flowing inwardly of the ends of the insulating housing 33, annular dams 38 are located on the end surfaces.

Referring now particularly to the left end of the insulating housing 33, as shown in FIG. 5A, it will be observed that the annular dam 38 has an annular surface 39 in engagement therewith which is provided on a pan shaped diaphragm 40 that is formed preferably of thin copper. The diaphragm 40 has a flat bottom 41 and an outilared rim 42 which overlies the platinum band 36. A filling of molten solder 43 is provided between the platinum band 36 and the outflared rim 42, as shown, to seal hermetically the diaphragm 40 to this end of the insulating housing 33. It will be understoood that the annular dam 38 limits the extent of flow of the solder 43 essentially to the position shown. Extending outwardly from the flat bottom 41 of the diaphragm 40 and offset from the central portion thereof is a tubular extension 44 having a radially outwardly extending flange 44 which is brazed at 45 to the flat bottom 41.

Considering now the right end of the insulating housing 33, it will be noted that it is closed off or hermetically sealed by a pan shaped diaphragm] that is indicated, generally, at 46. The diaphragm 46 includes an annular portion 47 that is formed of thin copper and it has an annular surface 43 for engagement by the annular dam 38 and an outflared rim 49 for receiving the solder 50 that is employed for joining the annular portion 47 to theinsulating housing 33. The annular portion 47 also includes a cylindrical portion 51 that terminates in a grooved end portion 52 with which aback up plate 53, formed preferably of brass, cooperates. It will be understood that the back up plate 53 provides the bottom of the pan shaped diaphragm 46 and it will be observed that it has an annular groove 54 which provides a thin annular rim 55 for inte'rfitting with the grooved end portion 52 where it is secured by solder 56.

Mechanical connection to the ends of the insulating housing 33 is provided by adapter rings 57 which, it will be understoood, form parts of the terminals 34 and 35.

The adapter rings 57 have corrugated inner surfaces 58 for receiving etween them and the juxtaposed end surface of the insulating housing 33 including the sand bands 37 fillings of Portland cement 59.

As an initial step in the assembly of the current interrupter 32 the insulating housing 33 has the pan shaped diaphragm 46 applied and secured thereto in the manner described by the soldered joint 43. Likewise at the other end the annular portion 47 of the pan shaped diaphragm 46 is applied. It will be understood that the back up plate 53 is not applied at this time, thereby leaving this end of the insulating housing 33 open for insertion of the separable contact structure to be described. Another part of the preliminary assembly involves the application of the adapter rings 57 with the Portland cement 59 securing them mechanically in place. Preferably this sub-assembly is completed as an entity and then it is used to make the complete assembly of the current interrupter 32.

The internal details of construction of the current interrupter 32 now will be described, particularly with reference to FIGS. SA-SB of the drawings. Here it will be observed that there is provided within the insulating housing 33 a rigid separable contact structure that is in dicated, generally at 62. The rigid separable contact structure 62 includes separable main contacts, shown generally at 63, in parallel with separable auxiliary contacts, shown generally at 64. It will be understood that provision is made for first opening the separable main contacts 63 and then transferring the entire current flow to the auxiliary contacts 64 which are opened quickly in the filling of arc extinguishing gas under pressure to complete the final circuit interruption. On reclosure the main contacts 63 are closed simultaneously with closure of the auxiliary contacts 64. The operation of the main and auxiliary contacts 63 and 64 is under the control of the mechanism within the mechanism housing 19 as determined by rotation of the shaft 18, all as described in the application above referred to, now Patent No. 3,030,481. The separable main contacts 63 are mounted at one end on a heavy gauge copper tube 65 which extends through the tubular extension 44 that is brazed to the flat bottom 41 of the pan shaped diaphragm 40. That portion of the copper tube 65 which extends into the tubular extension 44 is securely clamped thereto and to the terminal 34 by a terminal end adapter 66 which mates with the adapter ring 57 and is rigidly secured thereto by bolts 67. It will be understood that the terminal end adapter 66, which is preferably formed of good conducting mate rial, such as aluminum, and the adapter ring 57 complete the assembly of the terminal 34.

As shown more clearly in FIGS. 5A and 9 of the drawings the terminal end adapter 66 is provided with an integrally formed semi-circular section 68 which mates with a semi-circular section 69 that forms an integral part of a terminal end support 70 that is formed of good conducting material, such as copper. The terminal end support 70 has a pad portion 71 for mounting on the line terminal 31 as shown more clearly in FIG. 4 of the drawings by bolts 72. The semi-circular sections 68 and 6h, FIG. 9, are drawn toward each other by bolts '73 with the result that the end of the heavy gauge copper tube 65 and the tubular extension 44 are securely clamped together and to the terminal 34. Since the heavy gauge tube 65 is securely clamped to the terminal 34 in the manner described and since the copper tube 65 forms one support for the rigid separable contact structure 62, it will be apparent that the latter is rigidly supported Within the insulating housing 33 at one end on the terminal 34.

The other end, FIG. 5B, of the separable main contacts 63 is mounted on a heavy gauge copper tube 75 that extends through the back up plate 53 and is brazed thereto as indicated at 76. It will be understood that the copper tube 75 is brazed to the back up plate 53 as a part of a sub-assembly of the rigid separable contact structure 62 and before the back up plate 53 is soldered at 56 to the pan shaped diaphragm 46.

At the inner ends of the copper tubes 65 and 75 there are provided main stationary contact structures that are indicated, generally, at 77. They are of duplicate construction and a description of one sufiices for both. Each main stationary contact structure 77 includes a contact tube 78 which telescopes within the respective end of the tubes 65 or 75 and is brazed thereto as indicated at 79. The other end of the contact tube 78 is longitudinally slotted to provide contact fingers 8b which are urged inwardly by leaf springs 81 which are individual to the respective contact fingers 8i and which are surrounded by a retainer ring 82 against which the leaf springs 81 react. The inward movement of the contact fingers 8b is limited by a spreader ring 83.

In order to interconnect the main stationary contact structures 7777 at the inner ends of the copper tubes 65 and 75 which extend inwardly from and are connected to the terminals 34 and 35, a main movable contact 86 is provided. It is of generally cylindrical shape, is formed of copper and has enlarged end portions 87-87 which, in the closed position, are engaged by the contact fingers 86 of the respective main stationary contact structure 77 under substantial contact pressure. The main movable contact 86 is operated to the open position by movement out of engagement with the main stationary contact structure 77 on the tube 65 and through the other main stationary contact structure 77 into the tube 75. For this purpose an operating rod insert 88, preferably formed of stainless steel, extends into one end of the main movable contact 86 and is secured thereto by a locking pin 89. At its other end the operating rod insert 83 is telescoped into a rod-like operator 90 in the form of a tube of stainless steel and they are brazed together as indicated at 91. It will be observed that the rod-like operator @0 extends through the back up plate 53 and to a position outside of the terminal for connection to the operating mechanism within the mechanism housing 19. The projecting end of the operator 90 has an annular ring 92 secured thereto adjacent a slotted end portion 93. A threaded bushing 94 is slidable on the projecting end of the operator 90 for attaching it to the operator within the mechanism housing 19. It will be understood that the slotted end portion 93 is connected to the main operating arm 324 that is shown in FIGS. 35 and 47 of Patent No. 3,030,481 which is biased to open position by the springs 332 and 333 of this patent.

Since the insulating housing 33 is filled with are extinguishing gas at a pressure above atmospheric pressure, it is essential that there be provided a seal between the rod-like operator 9i) and the back up plate 53. For this purpose a hermetic seal assembly is provided which includes an end guide washer 97 that is brazed to the operating rod insert 88 at 91 where the operating rod insert 38 also is brazed to the end of the rod-like operator 90. Since the main movable contact 86 has a stroke of the order of 4" or more between closed and open position, it is necessary to accommodate this relatively great movement by hermetic sealing means. For this purpose four beryllium copper bellows units 98 are employed. The left end of the left bellows unit 98 is soldered to the end guide washer 97. Intermediate guide washers 99, preterably formed of brass, are slidably mounted on the rod like operator 9% between the juxtaposed ends of the bellows units 98 and the ends thereof are soldered thereto.

It has been found that the bellows units 9 8 are subject to severe vibration incident to the movement of the rodlike operator fit in opening and closing the main movable contact 86. Travelling waves of mechanical movement are set up in the bellows units 98 and they are accentuated because of the overall length thereof. In order to minimize these vibrations, tubular spacers 169, preferably formed of brass, are brazed at 161 to the intermediate guide washers 99. The tubular spacers lilil are of such a length that they extend part way between the intermediate guide washers 99 when the main movable contact is in the closed position as indicated in FIG. 5B of the drawings. Movement of the guide washers 99 toward each other is limited by the tubular spacer 109 and they also hold the respective guide washers in transversely aligned relation on the operator 99. This construction also prevents crushing of the convolutions of the bellows units 98. At the right end of the bellows unit 93 and within the tube 75 there is provided an annular end plate 162. It is brazed at 103 to the juxtaposed end of the adjacent bellows unit 98 and is soldered at 104 to the adjacent end of the tube 75. Within the right bellows unit 93 there is provided a tubular spacer 105 which cor responds to the tubular spacers 1%, previously described, and. it has an annular flange 106 which overlies the inner periphery of the end plate 162. It has been found that the vibrations of the bellows units 98 are further damped by the provision of a spiral bumper spring 107. It will be observed that the spiral bumper spring 107 is located between the annular flange 106 on the spacer 195 and the inner side or a bushing 198 of suitable plastic material through which the rod-like operator 9%? projects and is slidable. The bushing 108 is held in place by a clamp nut 109 which is applied as a part of the final assembly of the current interrupter 32.

As pointed out, there is provided within the insulating housing 33 a rigid separable contact structure 62 which includes support plates 112-112 in spaced relation. One of them is shown in FIG. 6. Hence it will be observed that each of the support plates 112, which are formed preferably of aluminum, has an opening 113 for receiving the tube 65 or the tube 75 as the case may be. The support plate 112 is slotted as indicated at 114 and a cap screw 115 is provided for clamping the support plate 112 to the tube 65, for example. In the upper portion of each support plate 112 there is a semi-circular opening 116 with which a cap member 117 having a similar opening cooperates for clamping an adapter plate 119 therein. The cap member 117 is clamped in place by cap screws 118. With a view to centering the support plate 1E2 within the cylindrical opening through the insulating housing 33 radially extending bumpers 120 are provided and are secured in place on the cap member 117 and on the support plate 112 by pins 121. The bumpers 120 are formed preferably of suitable plastic insulating material and the arrangement is such that their rounded outer ends are juxtaposed to the inner cylindrical surface of the insulating housing 33.

- The support plate 112112, as shown in FIG. 7, have an insulating bridging structure, shown generally at 124, therebetween. This bridging structure is formed by a pair of insulating rods 125--125 that are composed of suitable insulating material such as porcelain. Insulator support posts 126 and 127 are cemented into the ends of the insulating rods 125-425. The insulator support posts 126 are formed of aluminum and are threaded as indicated at 128 into one of the support plates 112 while the aluminum insulator support posts 127 at the other end extend through clearance openings 129129 in the associated support plate 112. The assembly is clamped in place by clamp nuts 130. It will be understood that the insulating bridging structure 124, provided by the insulating rods 125125 secured at their ends to the support plates 112112 in the manner described and the copper tubes 65 and 75, provides a principal portion of the rigid separable contact structure 62 which is mounted on the back up plate 53 for insertion through one end of the insulating housing 33. It remains to describe the construction of the separable auxiliary contacts 64 and the gas circulating means associated therewith.

It will be recalled that the separable contact structure 62 is provided with separable auxiliary contacts 64 that are connected in parallel with the separable main contacts 63, previously described. The details of construction relating to the separable auxiliary contacts 64 now will be set forth. As shown in FIGS. A and 6 of the drawings, the adapter plate 119 which is clamped by the cap member 117 securely to the support plate 112, is provided with a laterally extending guide stem 131 of insulating material. The guide stem 131 is rigidly secured to the adapter plate 119 and it is employed for carrying a relatively stationary auxiliary contact, shown generally at 132. Part of the auxiliary contact 132 is shown in FIG. 5A and the balance is shown in FIG. 5B. It will be observed that in includes a contact tube 133 of good conducting material such as copper and that it has a terminal 134 at its left end which is connected by a flexible cable 135 to a cable lug 136 which is suitably secured to the support plate 112. In this manner the contact tube 133 is provided with a good con ducting path over the flexible cable 135 to the support plate 112 and from it by the copper tube 65 to the terminal 34. The contact tube 133 is slidable endwise on the guide stem 131 to a limited extent. A transverse pin 137 cooperates with a shoulder 138 on the guide stem 131 to limit the movement of the contact tube 133 away from the adapter plate 119. Normally the contact tube 133 is biased away from the adapter pate 119 by a coil compres sion spring 139 positioned therewithin and reacting between it and the guide stem 131. At the right end of the contact tube 133 there is provided a contact tip 140 of suitable arc resisting metal.

Cooperating with the relatively stationary auxiliary contact 132 is a relatively movable auxiliary contact which is indicated, generally, at 142. It includes an annular cont-act tip 143 of arc resisting material that is arranged, as shown in FIG. SE, to have contact engagement with the contact tip 40. The relatively movable auxiliary contact 142 also includes a contact tube 144, preferably formed of copper, which carries at its left end the contact tip 143 and at its right end is telescoped within a central hub portion of a contact carrier 145 that is formed preferably of aluminum. The left end of an operating rod insert 88, generally of the same construction as the operating rod insert 88 previously described in connection with the separable main contacts 63, is secured by a locking pin 89 to the contact carrier 145. Also, the operating rod insert 88 is secured to a rod-like operator 90, a duplicate of the rod-like operator 9%) described previously, with the resultthat the contact carrier 145 and relatively movable auxiliary cont act 142 mounted thereon are moved as a unit for opening the circuit at the separable contacts 64. It will be understood that the slotted end portion 93 associated with the operating rod insert 88 that is connected to the contact carrier 145 is connected to the auxiliary operating arm 346 that is shown in FIGS. and 44 of Patent No.

3,030,481 which is biased to open position by the auxiliary spring 343 of this patent assisted under certain circumstances there related by kinetic energy incident to movement of main operating arm 324 under the biasing action of springs 332 and 333. Essentially the same bellows arrangement is provided for sealing the operator associated with the relatively movable auxiliary contact 142 that is employed for hermetically sealing the operator '90 employed for controlling the movement of the main movable contact 86. However, it will be observed that the right bellows unit 98 is provided with the end plate 102 which is soldered at 104 to a relatively short coupling tube 147 that is suitably brazed to the back up plate 53.

It is desirable that the gas filling the insulating housing 33 be circulated therein and in particular that it be applied to the arc space which is formed on separation of the contact tip 143 of the relatively movable auxiliary contacts 142 from the contact tip of the relatively stationary auxiliary contact 132. For this purpose a pump, shown generally at 148, is provided which is operated as a result of movement of the contact carrier when the operator 91) connected thereto is withdrawn from the insulating housing 33. The pump 143 includes a pump cylinder 149, preferably formed of brass, which is telescoped for a slight extent at its right end over the left end of the coupling tube 147 and bears against the back up plate 53 with the result that this end of the pump cylinder 149 is completely closed 011. The pump cylinder 149 is of the same external diameter as the adapter plate 119 and it is clamped to the associated sup port plate 112 by its cap member 117. Slidably mounted within the pump cylinder 149 is a piston cylinder 156 that may be formed of aluminum and its left end is secured, as shown in FIG. SE, to the contact carrier 145 so that it moves conjointly therewith. Piston rings 151-151, prefer-ably formed on insulating plastic material, are carried a by the piston cylinder for guiding it in its movement within the pump cylinder 149 and also for insulating it therefrom in order that current will not flow directly therebetween. It will be observed that openings 152 are formed in the contact carrier 145 with the result, as it is moved together with the piston cylinder 150 into the pump cylinder 149, that the arc extinguishing gas therein is compressed and caused to flow therefrom through the openings 152. Part of the gas flows through transverse openings 144' into the contact tube 144 and out of the opening in the annular contact tip 143. The left end of the contact carrier 145 is threaded, as indicated at 153, for receiving a nozzle 154 that is formed of suitable insulating material and is employed for directing the flow of arc extinguishing gas from the openings 152 into the arc space that is formed between the contact tips 140 and 143 on opening of the circuit.

It will be understood that the rigid separable contact structure 62 is assembled exteriorly of the insulating housing 43. In particular, the parts associated with the separable main cont-acts 63 and with the separable auxiliary contacts 64 are assembled on the back up plate 53. They are inserted into the insulating housing from the right end through the opening in the pan shaped diaphragm 46 defined by its annular portion 47 with the left end of the copper tube 65 extending into the tubular extension 44 of the pan shaped diaphragm 40 to the extent indicated. Prior to the application of terminal end adapter 66 at the left end, FIG. 5A, the flat bottom 41 is covered with a layer 157 of grease to prevent a filling 158 of epoxy resin on the juxtaposed inner side of the terminal end adapter 66 from adhering to the pan shaped diaphragm 41). By providing the filling of epoxy resin 158 it is possible to provide a tight fit without any voids between the juxtaposed portions of the pan shaped diaphragm 4t and the terminal end adapter 66.

Following the insertion of the rigid separable contact structure 62 in the manner described, the back up plate 53 is sealed to the grooved end portion 52 by the solder 56 thereby completing the hermetic seal at the right end of the insulating housing 33. Next a mechanism end adapter 159, formed of suitable good conducting metal such as aluminum, is applied to the adapter ring 57 and it completes the terminal 35. It is clamped in place by bolts 160 so that the central portion thereof overlies and has close contact surface engagement with the juxtaposed portion of the back up plate 53.

To insure against loss of contact between end adapter 159 and back up plate 53 due to temperature change, a spring plate 161, FIGS. 11 and 12, is provided having openings 162 for receiving therethrough the right ends of the copper tube 75 and of the coupling tube 147 which project through the flat bottom of the mechanism end adapter 159. It will be observed that these ends are threaded as indicated at 163 and 164 for receiving the clamp nuts 1119. Initially, as indicated in FIG. 11, the spring plate 161 is slightly bowed at the center. It is flattened out, as shown in FIG. B, on tightening of the clamp nuts 169.

At the other end of the insulating housing 33, the left end of the copper tube 65 is rigidly clamped to the terminal 34 on tightening of the bolts 73 to draw the semicircular sections 68 and 69 securely against the periphery of the tubular extension 44 and the left end of the copper tube 65 therewithin.

It is desirable that provision be made for removing the acidic portion of the arc extinguishing gas which results from partial decomposition thereof when it is subjected to the are drawn on separation of the auxiliary contacts 64. For this purpose gas clean up units 167-467 are provided, as indicated in FIGS. 5B and 8 of the drawings, between the pump cylinder 149 and the copper tube 75. The gas clean up units 167-167 preferably include cylinders 168 of activated alumina positioned between end plates 169-469 in which through bolts 17(i-170 extend that are interconnected by end straps 171-171. If desired, instead of activated alumina, calcium carbonate can be employed. Also sodium hydroxide can be combined with activated alumina for clean up purposes.

It is desirable to provide for indicating at a substantial distance from the switch means whether the pressure of the arc extinguishing gas Within the housing 33 remains at a predetermined pressure or whether it has fallen below this pressure as the result of leakage. For this purpose, as shown in FIGS. 5A and 10, indicating means, shown generally at 174, is provided. The indicating means 174 is also disclosed and claimed in copending application Serial No. 118,620, filed June 21, 1961, now Patent No. 3,077,527, issued February 12, 1963. The indicating means 174 includes pressure sensitive means 175 in the form of an inner closure or Washer that is subject directly to the pressure of the gas within the insulating housing 33. It will be noted that the pressure sensitive means 175 is located at the outer end of the copper tube 65. Since the inner end of the copper tube 65 is in communication with the interior of the insulating housing 33, the pressure applied to the pressure sensitive means 175 is the pressure within the insulating housing 33. It will be noted that the pressure sensitive means 175 is centrally apertured for a purpose that will be apparent presently. It is soldered at 176 to one end of a beryllium copper bellows 177 the other end of which is brazed at 178 to a closure plate 179, formed preferably of copper, which is soldered at 180 to the outer end or the tubular extension 44. In this manner the hermetic sea] at the left end of the insulating housing 33 is completed.

The closure plate 179 has a central aperture 181 through which a filler tube 182 extends. The filler tube 182 functions not only for the purpose of introducing the arc extinguishing gas into the insulating housing 33 but also as a rod like member in a manner described hereinafter for controlling the operation of the indicating means 174. At its inner end the filler tube 182 is brazed at 133 to the pressure sensitive means or washer and, since its inner end opens into the insulating housing 33, the latter can be filled with arc extinguishing gas to the desired pressure by connecting a supply thereof to the outer end. A coil compression spring 184 surrounds the filler tube 182 and extends between the pressure sensitive means 175 and the closure plate 179 to bias them apart. Near its outer end the filler tube 182 is pinched off at 135, after the insulating housing 33 has been filled to the desired pressure by the arc extinguishing gas.

Now it will be apparent since the filler tube 182 is freely movable through the aperture 181 in the closure plate 179 and since the gas pressure within the insulating housing is applied to the pressure sensitive means 175, the latter will be positioned in accordance with the gas pressure. When the insulating housing 33 is filled with are extinguishing gas at the predetermined pressure, the coil cornpression spring 184 is compressed and the pressure sensitive means 175 occupies a position in minimum spaced relation with respect to the closure plate 179. Now, when the gas pressure within the insulating housing 33 decreases, the pressure exerted on the pressure sensi. tive means 175 inside the insulating housing 33 is correspondingly decreased. As a result it moves away from the closure plate 179 carrying with it the tiller tube or rod-like member 192.

Advantage is taken of the relative movement of the tiller tube or rod-like member 182 from the position shown in PKG. 5A of the drawings corresponding to predetermined pressure or" gas within the insulating housing 33 to an alternate position at predetermined lower pressure for controlling the movement of a latch 188, in turn, to control the operation of the indicating means 174. As shown in FIG. 1% the latch 178 includes a portion 189 which extends around the filler tube or rod-like member 132 and is secured thereto against relative longitudinal movement by ciamp screws 190. Thus the latch 188 has a translatory movement toward the outer side of the closure plate 179 on decrease in the pressure of the are extinguishing within the insulating housing 33. As long as the latch 188 is held substantially in the position shown as the result of predetermined gas pressure within the insulating housing 33 and during a predetermined reduction thereof, it engages a stop bracket 191 which extends radially inwardly from and is secured by rivets 192 to an indicator drum 193. The indicator drum 193 is mounted at its left end by a cylindrical support plate 194 which has an inwardly extending hub 195 that is journaled on hearing sleeves 195-196 which are mounted on a shaft 197. The shaft 197 has a head 198 at its inner end and its other end extends through an opening 199 in an end Wall of a housing 2%, preferably formed of aluminum. The housing 2% has a rectangular base flange 201, FIG. 10, that is held by bolts 292 in position on the semi-circular sections 68 and 69 of the terminal 66 and the terminal end support 7 9, respectively.

It will be noted that the outer end of the shaft 197 is threaded at 293 for receiving a nut 264 to clamp it in position against rotation on the outer end of the housing 290. lrerf 295 is located in the outer end of the shaft 197 for receiving a screw driver to adjust its position and for tensioning aspiral spring 2&6 which extends around the hub 195 and is secured at its inner end to the head 198 and at its other end to the cylindrical support plate 194. With the nut 264 loosened, a screw driver is inserted in the kerf 295 to rotate the shaft 197 and tension the spring 206 in order to hold the stop bracket 191 under tension against the latch 138. Then the nut 204 is tightened.

In this position of the indicator drum 193 a first reflective indicator means 207, FIG. 10, is visible through an opening 208 in the housing 201). Preferably the first indicator means 2127 is colored green and may comprise an appropriately colored sheet of reflective adhesive material which extends lengthwise over the indicator drum 193 for one half of its circumference. Since the opening i 298 is somewhat less in arcuate length than the arcuate length of the first indicator means 267, only the color thereof is visible through the opening 2%.

Should the gas pressure within the insulating housing 33 decrease to such an extent that the latch 188 is moved toward the closure plate 179 and entirely out of engagement with the stop bracket 1%, the spring 206 then rotates the indicator drum 193 in the direction indicated by the arrow 2%, FIG. 10. This removes the first reflective indicator means 2'07 from view through the opening 208 and brings a second reflective indicator means 21! of reflective adhesive material into view. Preferably it is colored red. In order to stop the rotation of the indicator drum 193 in a position where only the second indicator means 21% will be visible through the opening 288, a second stopbracket 211 is secured by rivets 212 to the indicator drum 193. It will be noted that the second stop bracket 211 is offset from the first stop bracket 191 so that it will be in a position to be intercepted by the latch 188 in its retracted position corresponding to a predetermined lowered pressure within the insulating housing 33. The latch 183 is of sufiicient length to maintain latching engagement with the stop bracket 191 under varying pressures due to temperature change to the end that a substantial pressure change, greater than that due to change in temperature, is required to disengage the stop bracket 191 and indicate actual loss of arc extinguishing as. g It is desirable to protect the indicator drum 193 from the weather. For this purpose a transparent cylinder 213 is employed. It can be formed of suitable transparent plastic material; Gaskets 214 and 215 are provided at the ends of the cylinder 213 to provide a weather tight construction. .It will be observed that the gasket 215 surrounds the projecting end of the tubular extension 44 and underlies a beveled end of the transparent cylinder 213.

When the interior of the insulating housing 33 is filled with the arc extinguishing gas under pressure of the order of 2 atmospheres, there is a substantial pressure applied to the main and auxiliary movable contacts 86 and 142 and the parts movable therewith in a direction to bias them toward the open position. This pressure may be of the order of to pounds applied to each movable contact assembly. It is advantageous to have these biasing forces present to assist in the opening of the main and auxiliary contacts 63 and 64. It will be recalled that the rod-like operators 90-90 are hermetically sealed, by the bellows units 98 individual thereto, to the terminal 35. The interiors of the bellows units hit communicate directly with the atmosphere and it can be stated that the eifective area subject to the pressure of the arc extinguishing gas is the mean of the areas of circles corresponding to the outside diameter and inside diameter of the bellows units 98.

As pointed out above, the kinetic energy incident to movement of the main operating arm 324 of Patent No. 3,030,481 and thus incident to the movement of the main movable contact 86 of the instant construction is available for assisting in opening the auxiliary movable contact 1&2. Since the pump cylinder 149 is secured to the contact carrier 145, the operation of the pump 148 in causing the arc extinguishing gas to flow into the arc space between the contact tips 14-0 and 143 is facilitated and pressure commensurate with such operation is available to cause the gas to flow into are thus overcoming pressure caused by the arc and reacting against the contact carrier 145 and parts movable therewith in a direction resisting operation of the pump 14% and separation of the auxiliary contacts 641.

In FIGS. l3Al3B, there is indicated, generally, at 2.17

a current interrupter which corresponds to the current interrupter 32 previously described. It will be recalled that the current interrupter 32 includes a single set of separable main contacts 63 in parallel with a set of separable auxiliary contacts 64. In the current interrupter 217 two sets of separable main contacts 63 are provided in tandem and are connected in series circuit relation and in parallel therewith are two sets of separable auxiliary contacts 64 also in tandem. Except for the changes necessary to accommodate the two sets of series connected contacts 63-d3 and e s-64; and to provide for proper voltage division therebetween, the details of construction of the current interrupter 217 are essentially the same as for the current interrupter 32. Wherever possible the same reference characters are applied to the same elements in order to avoid duplication of the description.

Within the insulating housing 33 which, except for its length, is identical with the insulating housing 33 previously described there is provided a rigid separable contact structure that is indicated, generally, at 213. As just pointed out, this contact structure employs two sets of separable main contacts 6363 in series and in parallel therewith there are two sets or separable auxiliary contacts 64-64, each being provided with a pump 148 for circulating the arc extinguishing gas and causing it to flow in the arc space between each set of separable auxiliary contacts at. in this construction a relatively short copper tube 65 is employed instead of the relatively long copper tube 65 previously described. The relatively short copper tube 65' extends into the tubular extension 44 and is clamped thereto in the same manner previously described for the copper tube 65. In addition, the same indicating means 174, previously described for detecting when the gas pressure falls below a predetermined value, is employed.

Since two sets of separable main and auxiliary contacts 63-d3 and 64-64 are employed in series, four support plates 112 are provided, two plates 112-412 being employed for each set of parallel contacts 63 and 64. Also, because the sets of contacts 63-63 and 64-64 are con nected in series, provision is made for distributing the voltage therebetween when they are opened. For this purpose one of the insulating rods of each pair is provided with a high resistance coating 219 so as to provide a resistance of several megohms between the ends. Contact springs 22ti-220 serve to interconnect the ends of the high resistance coating 219 to the respective support plates 112l12 at the ends. In order to protect the resistance coating 219 from the are products each of them is surrounded by an insulating tube 221, preferably formed of high heat resisting material such as glass.

Interconnecting the two center support plates lil2112 is a heavy gauge copper tube 222. At its ends there are provided main stationary contact structures 77-77 which cooperate, respectively, with the main movable contacts 8686. An operating rod 22.3 of insulation interconnects the main movable contacts 86-86 for conjoint operation on movement of the associated rod-like operator 90 under the control of the mechanism in the mechanism housing 19.

With a View to eifecting conjoint operation of the relatively movable auxiliary contacts 142442 of the two sets of separable auxiliary contacts 6 3-64, each of the associated contact carriers -145 is provided with integrally formed diametrically laterally extending arms 226-226 which, as shown in FIGS. ISA-15B, are mechanically interconnected by insulating rods 227227. The insulating rods 2274227 extend through the two intermediate support plates 112112 and are guided thereon by insulating guide bushings 228-228 FIG. 14-. The extreme ends of the insulating rods 2 27-227 are provided with flanged fittings 229229 which, as shown in FIG. 15A. overlie opposite sides of the respective arms 226-226 from the contact carriers 145l45 with 0 rings 230 239 therebetween to absorb some of the shock. incident to rapid acceleration and deceleration of the insulating rods 227427 and parts associated therewith.

Also extending between and clamped to the intermediate support plates llll2112 is the pump cylinder 149 which is associated with the pump 14% at the left end of the insulating housing 33. It is held in place on the inter- 13 mediate support plates 112l12 by the cap members 117-1l7.

It is necessary to interconnect the separable auxiliary contacts 64-64. For this purpose, as shown in FIG. 13A, a terminal 233 extends from the contact carrier 145 there shown and it receives one end or a flexible cable 234- which extends through the associated pump cylinder 149 to a terminal 235' that extends from the adapter plate 119 shown in FIG. 13B.

In order to accommodate the arms 226-226 extending from each of the contact carriers 145l in their movement to the full open position, longitudinally extending slots 23d-236 are provided in the respective pump cylinders 149-149. Thus it is possible to obtain a full opening stroke of the order of four to five inches on operation of respective rod-lil-ie operator 913 for each of the main auxiliary contacts 6363 and 6464. In the open circuit position the two resulting gaps in series are bridged by the high resistance coatings 2194219 on one of each of the pairs of insulating rods 125-125 with the result that the voltage applied between the terminals 34 and 35 under these conditions is divided in a predetermined manner across the respective open contacts.

It will be observed that the insulating rods 22.722"7 mechanically interconnect the contact carriers 145-445 to which the relatively movable auxiliary contacts 142142, the piston cylinders l5"9 of the pumps 14li-ll8, and the nozzles led-15d are rigidly connected. This construction insures that these parts always move in unison and cannot get out or step as a result of the generation within the insulating housing 33 of gas pressure due to the heat of the arcs drawn on separation of the auxiliary contacts tid64 or other forces which might be applied unequally to the moving parts of the separable contact structures 218. Thus the lengths of the gaps for the auxiliary contacts 6464 are always the same and the arc extinguishing efforts at the gaps caused by the flow of arc extinguishing gas through the respective nozzle 154 by the respective pump 148 are substantially identical.

Since the kinetic energy incident to the opening movement of the main contacts 63- 3 is available in connection with the opening of the auxiliary contacts 64-64 and the operation of the pump 148-14ti in the embodiment shown in FIGS. l3A-13B for the reason above outlined in regard to the embodiment shown in FlGS. SA-SB, the gas pressures caused by pumps 148143 are such as to provide the required gas flows into the two arcs that are drawn on opening of the auxiliary contacts 63 as.

Since the main movable contacts ss ss are positively mechanically interconnected by the insulating operating rods 223, they move in unison and the gaps for the main contacts 63-63 are always of the same length.

What is claimed as new is:

l. in a circuit interrupter, in combination, a cylindrical irangible insulating housing, hermetic sealing means closing off each end of said housing, an arc extinguishing gas'within said housing at a pressure above atmospheric pressure, a terminal having a bottom portion surrounded by an annular flange telescoped over each end of said housing, cement securing each flange to the respective end or" said housing, said hermetic sealing means at each end of said housing being independent of the attachment by cement of the terminal and annular flange to the respective end of said housing, separable contact means within said housing interconnecting said terminals, an operator for opening and closing said contact means extending out of one end of said housing through the hermetic sealing means thereat, said hermetic sealing means at said one end including a seal between said operator and the hermetic sealing means through which it extends.

2. In a circuit interrupter, in combination, a cylindrical frangible insulating housing hermetic sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, a terminal having a bottom portion surrounded by an annular flange telescoped over each end of said housing, cement securing each flange to the respective end of said housing said hermetic sealing means at each end of said housing being independent of the attachment by cement of the terminal and annular flange to the respective end of said housing, separable contact means within said housing interconnecting said terminals, an operator movable endwise of said housing and extending out of one end thereof through the hermetic sealing means thereat for opening and closing said contact means, said hermetic sealing means at said one end including flexible bellows means telescoped With said operator and between said operator and the hermetic sealing means through which it extends.

3. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, hermatic sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, said hermetic sealing means including a pan shaped diaphragm member having an annular flange overlying the respective outer end portion of said housing and soldered thereto, a terminal having a bottom portion surrounded by an annular flange telescoped over each end of said housing, cement securing each flange to the respective end of said housing, said hermetic sealing means at each end of said housing being independent of the attachment by cement of the terminal and annular flange to the respective end of said housing, separable contact means within said housing interconnecting said terminals, and an operator for opening and closing said contact means extending out of one end of said housing through the hermetic sealing means thereat.

4. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, hermetic sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, said hermetic sealing means including a pan shaped diaphragm member having an annular flange overlying the respective outer end portion of said housing and soldered thereto, one of said diaphragm members including a back up plate having an annular peripheral flange extending toward the end of said housing adjacent thereto for receiving an annluar reentrant portion of associated diaphragm member and soldered thereto at a location remote from the juncture of associated diaphragm member and said housing, a terminal having a bottom portion surrounded by an annular flange telescoped over each end of said housing, cement securing each flange to the respective end of said housing, said hermetic sealing means at each end of said housing being independent of the attachment by cement of the terminal and annular flange to the respective end of said housing, separable contact means within said housing interconnecting said terminals, and an operator for opening and closing said contact means extending out of one end of said housing through the hermetic sealing means thereat.

5. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, hermetic sealing means closing oil each end of said housing, an arc extinguishing gas Within said housing at a pressure above atmospheric pressure, a terminal having a bottom portion surrounded by an annular flange telescoped over each end of said housing, cement securing each flange to the respective end of said housing, said hermetic sealing means at each end of said housing being independent of the attachment by cement of the terminal and annular flange to the respective end 0' said housing, separabl contact means within said housing interconnecting said terminals, an insulating structure within said housing bridging said contact means and forming therewith a rigid unitary structure, and an operator for opening and closing said contact means exsneavse i; tending out of one end of said housing through the hermetic sealing means thereat.

6. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, hermetic sealing means closing oit each end of said housing, and are extinguishing gas within said housing at a pressure above atmospheric pressure, pan shaped terminals telescoped over and closing oi? the ends of said housing and rigidly secured thereto, said hermetic sealing means at each end of said housing being independent of the attachment of said pan shaped terminals to the respective end of said housing, a unitary separable contact structure in said housing interconnecting said terminals with the ends extending through the associated hermetic sealing means, means rigidly clamping one end of said contact structure to one of said terminals, means resiliently coupling the other end of said contact structure to the other of said terminals, and an operator for opening and closing the contacts of said contact structure extending out of one end of said housing through the hermetic sealing means thereat 7. In a circuit interrupter, in combinatiorna cylindrical frangible insulating housing, hermetic sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, pan shaped terminals telescoped over and closing off the ends of said housing and rigidly secured thereto, said hermetic sealing means at each end of said housing being independent of the attachment of said pan shaped terminals to the respective end of said housing, a rigid conducting structure extending inwardly from each terminal through the respective hermetic sealing means including separable contact means and an insulating structure bridging said separable contact means, means rigidly clamping one end of said conducting structure to one of said terminals, means resiliently coupling the other end of said contact structure to the other of said terminals, and an operator for opening and closing said separable contact means extending out of one end of said housing through the hermetic sealing means thereat.

8. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, hermetic sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, pan shaped terminals telescoped over and closing off the ends of said housing and rigidly secured thereto, said hermetic sealing means at each end of said housing being independent of the attachment of said pan shaped terminals to the respective end of said housing, a rigid conducting structure extending inwardly from each terminal through the respective hermetic sealing means including separable contact means and an insulating structure bridging said separable contact means, said separable contact means having a travel of several inches between open and closed position, an operator for opening and closing said separable contact means extending out of one end of said housing through the hermetic sealing means thereat, and bellows means interconnecting said operator and the hermetic sealing means through which it extends and having a travel corresponding to said travel of said operator.

9. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, hermetic sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, pan shaped terminals telescoped over and closing off the ends of said housing and rigidly secured thereto, said hermetic sealing means at each end of said housing being independent of the attachment of said pan shaped terminals to the respective end of said housing, a rigid conducting structure extending inwardly from each terminal through the respective hermetic sealing means including parallel main and auxiliary separable contact means and an insulating structure bridging said separable contact means, and main and auxiliary operators for opening and closing said main and auxiliary separable contact means respectively, said operators extending out of one .irCi end of said housing through the hermetic sealing means thereat.

10. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, hermetic sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, pan shaped terminals telescoped over and closing oil the ends of said housing and rigidly secured thereto, said hermetic sealing means at each end of said housing being independent of the attachment of said pan shaped terminals to the respective end of said housing, a rigid conducting structure extending inwardly from each terminal through the respective hermetic sealing means including parallel main and auxiliary separable contact means and an insulating structure bridging said separable contact means, each of said separable contact means having a travel of several inches between open position and closed position, main and auxiliary operators for opening and closing said main and auxiliary separable contact means respectively, said operators extending out of one end of said housing through the hermetic sealing means thereat, and bellows means interconnecting each of said operators and the hermetic sealing means through which they extend and having a travel corresponding to said travel of the respective operator.

11. in a circuit interrupter, in combination, a cylindrical frangible insulating housing, sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, terminals at the ends of said housing, a relatively stationary contact mounted on one terminal and extending into said housing, a relatively movable contact in said housing for engaging and disengaging said relatively stationary contact, a rod-like conducting operator carrying said relatively movable contact at one end and at the other end extending through and slidably mounted on the other terminal, bellows means telescoped over said operator and secured at one end thereto and at the other end to said other terminal, tubular spacer means within said bellows means and slidable on said operator, and a coil compression spring interposed between said other terminal and the juxtaposed end of said spacer means for absorbing a portion of the shock incident to stopping of said operator at the end of its opening stroke,

12. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, terminals at the ends of said housing, a relatively stationary contact mounted on one terminal and extending into said housing, a relatively movable contact in said housing for engaging and disengaging said relatively stationary contact, a rod-like conducting operator carrying said relatively movable contact at oneend and at the other end extending through and slidably mounted on the other terminal, a plurality of bellows units telescoped in tandem over said operator, the innermost bellows unit having an end collar at its inner end secured to said operator, intermediate collars slidable on said operator and interposed between and secured to the juxtaposed ends of said bellows units, the outer end of the outermost bellows unit having connection with said other terminal, a tubular spacer within each bellows unit in spaced apart relation along and slidable on said operator,

and a coil compression spring interposed between said other terminal and the juxtaposed end of the outermost tubular spacer for absorbing a portion of the shock incident to stopping of said operator at the end of its opening stroke.

13. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, sealing means closing oil each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, terminals at the ends of said housing, main and auxiliary relatively stationary contacts mounted on one terminal and extending into said housing, relatively movable main and auxiliary contacts in said housing for engaging and disengaging said main and auxiliary relatively stationary contacts respectively, main and auxiliary rod-like conducting operators carrying said relatively movable main and auxiliary contacts respectively at one end and at the other end extending through and slidably mounted on the other terminal, bellows means telescoped over each operator and secured at one end thereto and at the other end to said other terminal, tubular spacer means within said bellows means and slidable on the respective operator, and a coil compression spring interposed between said other terminal and the juxtaposed end of the respective spacer means for absorbing a portion of the shock incident to stopping of the respective operator at the end of its opening stroke.

14. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, terminals at the ends of said housing, main and auxiliary relatively stationary contacts mounted on one terminal and extending into said housing, relatively movable main and auxiliary contacts in said housing for engaging and disengaging said main and auxiliary relatively stationary contacts respectively, main and auxiliary rod-like conducting operators carrying said relatively movable main and auxiliary contacts respectively at one end and at the other end extending through and slidably mounted on the other terminal, a plurality of bellows units telescoped in tandem over each operator, the innermost bellows unit having an end collar at its inner end secured to the respective operator, intermediate collars slidable on said operator and interposed between and secured to the juxtaposed ends of the respective bellows units, the outer end of each outermost bellows unit having connection with said other terminal, a tubular spacer Within each bellows unit in spaced apart relation along and slidable on the respective operator, and a coil compression spring interposed between said other terminal and the juxtaposed end of the respective outermost tubular spacer for absorbing a portion of the shock incident to stopping of the respective operator at the end of its opening stroke.

15. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, pan shaped terminals telescoped over and closing oii the ends of said housing and rigidly secured thereto, said sealing means at each end of said housing being independent of the attachment of said pan shaped terminals to the respective end of said housing, a relatively stationary contact mounted on one terminal and extending into said housing, a relatively movable contact in said housing for engaging and disengaging said relatively stationary contact, a rod-like conducting operator carrying said relatively movable contact at one end and at the other end extending through and slidably mounted on the other terminal, a metallic pump cylinder extending inwardly from said other terminal and overlying said operator, and a metallic piston cylinder slidable within said pump cylinder and having a nozzle portion rigidly secured to and movable with said operator for directing a stream of said gas into the space between said contacts on separation thereof resulting from movement of said operator outwardly of said housing.

16. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, sealing means closing off each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, pan shaped terminals telescoped over and closing oif the ends of said housing and rigidly secured thereto, said sealing means at each end of said housing being independent of the attachment of said pan shaped terminals to the respective end of said housing, a relatively stationary contact mounted on one terminal and extending into said housing, a relatively movable contact in said housing for engaging and disengaging said relatively stationary contact, a rod-lil e conducting operator carrying said relatively movable contact at one end and at the other end extending through and slidably mounted on the other terminal, a metallic pump cylinder extending inwardly from said other terminal and overlying said operator, a metallic piston cylinder slidable within said pump cylinder and having a nozzle portion rigidly secured to and movable with said operator for directing a stream of said gas into the space between said contacts on separation thereof resulting from movement of said operator outwardly of said housing, and piston ring means of insulating material interposed between said metallic cylinders and providing a sliding seal therebetween.

17. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, sealing means closing oif each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, pan shaped terminals telescoped over and closing oif the ends of said housing and rigidly secured thereto, a relatively stationary contact mounted on one terminal and extending into said housing, a relatively movable contact in said housing for engaging and disengaging said relatively stationary contact, a rod-like conducting operator carrying said relatively movable contact at one end and at the other end extending through and slidably mounted on the other terminal, a metallic pump cylinder extending inwardly from said other terminal and overlying said operator, a metallic piston cylinder slidable Within said pump cylinder and having a nozzle portion secured to and movable with said operator for directing a stream of said gas into the space between said contacts on separation thereof resulting from movement of said operator outwardly of said housing, and bellows means within said cylinders and telescoped over said operator, said bellows means being secured at one end to said operator adjacent said nozzle portion and at the other end to said other terminal.

18. In a circuit interrupter, in combination, a cylindrical frangible insulating housing, sealing means closing otf each end of said housing, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, pan shaped terminals telescoped over and closing off the ends of said housing and rigidly secured thereto, main and auxiliary relatively stationary contacts mounted on one terminal and extending into said housing, relatively movable main and auxiliary contacts in said housing for engaging and disengaging said main and auxiliary relatively stationary contacts respectively, main and auxiliary rod-like conducting operators carrying said relatively movable main and auxiliary contacts respectively at one end and at the other end extending through and slidably mounted on the other terminal, a tubular contact member extending inwardly from said other terminal and overlying said main operator for slidably receiving at its inner end one end of said main contact, a metallic pump cylinder extending inwardly from said other terminal and overlying said auxiliary operator, a metallic piston cylinder slidable within said pump cylinder and having a nozzle portion secured to and movable with said auxiliary operator for directing a stream of said gas into the space between said auxiliary contacts on separation thereof resulting from movement of said auxiliary operator outwardly of said housing, and bellows means telescoped over each operator and secured at one end thereto and at the other end to said other terminal.

19. In a circuit interrupter, in combination, a cylin drical insulating housing having hermetically sealed terminals at its ends and a filling of arc extinguishing gas under pressure, two pairs of conducting support plates in parallel spaced relation within and extending transversely of said housing, conducting support means extending from each terminal and rigidly mounting thereon the adjacent support plate of each pair, conducting support means rigidly interconnecting the adjacent support plates of each pair, insulator support means rigidly interconnecting said support plates of each pair, separable contact means interconnecting said support plates of each pair, operating means extending through one of said hermetically sealed terminals for moving said separable contact means simultaneously between open and closed position, and means providing a high resistance conducting path between each pair of support plates in shunt circuit relation to the respective contact means.

20. In a circuit interrupter, in combination, a cylindrical insulating housing having hermetically sealed terminals at its ends and a filling of arc extinguishing gas under pressure, two pairs of conducting support plates in parallel spaced relation within and extending transversely of said housing, conducting support means extending from each terminal and rigidly mounting thereon the adjacent support plate of each pair, conducting support means rigidly interconnecting the adjacent support plates of each pair, insulator support means rigidly interconnecting said support plates of each pair, separable contact means interconnecting said support plates of each pair, operating means extending through one of said hermatically sealed terminals for moving said separable contact means simultaneously between open and closed position, and means providing a high resistance conducting path between each pair of support plates in shunt circuit relation to the respective contact means, said insulator support means for each pair of support plates being in the form of a pair of rods of insulating material with one rod of each pair having a coating of high resistance conducting material extending from end to end to provide said high resistance conducting path.

21. In a circuit interrupter, in combination, a cylindrical insulating housing having hermetically sealed terminals at its ends and a filling of arc extinguishing gas under pressure, two pairs of conducting support plates in parallel spaced relation within and extending transversely of said housing, conducting support means extending from each terminal and rigidly mounting thereon the adjacent support plate of each pair, conducting support means rigidly interconnecting the adjacent support plates of each pair, insulator support means rigidly interconnecting said support plates of each pair, separable means interconnecting said support plates of each pair, operating means extending through one of said hermetically sealed terminals for moving said separable contact means simultaneously between open and closed position, means providing a high resistance conducting path between each pair of support plates in shunt circuit relation to the respective contact means, said insulator support means for each pair of support plates being in the form of a pair of rods of insulating material with one rod of each pair having a coating of high resistance conducting material extending from end to end to provide said high resistance conducting path, and an insulating sleeve telescopedjover said one rod of each pair to shield the coating of high resistance conducting material thereon from the products of the are drawn on opening of the respective separable contact means.

22. In a circuit interrupter, in combination, a cylindrical insulating housing having hermeticafly sealed terminals at its ends and a filling of arc extinguishing gas under pressure, two pairs of conducting support plates in parallel spacedrelation within and extending transversely of said housing, conducting support means extending from each terminal and rigidly mounting thereon the adjacent support plate of each pair, a pump cylinder stationarily mounted parallel to one of said conducting support means, a second. conducting support means rigidly interconnecting the adjacent supports plates of each palr, a second pump cylinder stationarily mounted parallel to said second conducting support means, insulator support means rigidly interconnecting said support plates of each pair, separable contact means interconnecting said support plates of each pair including a piston cylinder slidable within each pump cylinder and having a nozzle portion secured thereto for directing a stream of gas into the space provided by each separable contact means on opening thereof, insulating means mechanically interconnecting said piston cylinders for conjoint movement thereof, operating means extending from the piston cylinder in the first mentioned pump cylinder and through the adjacent hermetically sealed terminal for moving said separable contact means simultaneously between open and closed position, and means providing a high resistance conducting path between each pair of support plates in shunt circuit relation to the respective contact means.

23. In a circuit interrupter, in combination, a cylindrical insulating housing having hermetically sealed terminals at its ends and a filling of arc extinguishing gas under pressure, two pairs of conducting support plates in parallel spaced relation within and extending transversely of said housing, conducting support means extending from each terminal and rigidly mounting thereon the adjacent support plate of each pair, a pump cylinder stationarily mounted parallel to one of said conducting support means, a second conducting support means rigidly interconnecting the adjacent support plates of each pair, a second pump cylinder staitionarily mounted parallel to said second conducting support means, insulator support means rigidly interconnecting said support plates of each pair, separable auxiliary contact means interconnecting said support plates of each pair including a piston cylinder slidable within each pump cylinder and having a nozzle portion secured thereto for directing a stream of gas into the space provided by each separable auxiliary contact means on opening thereof, insulating means mechanically interconnecting said piston cylinders for conjoint movement thereof, auxiliary operating means extending from the piston cylinder in the first mentioned pump cylinder and through the adjacent hermetically sealed terminal for moving said separable auxiliary contact means simultaneously between open and closed position, separable main contact means also interconnecting said support plates of each pair, main operating means extending through said adjacent hermetically sealed terminal for moving said separable main contact means simultaneously between open and closed position, and means providing a high resistance conducting path between each pair of support plates in shunt circuit relation to the respective contact means.

24. In a circuit interrupter, in combination, a cylindrical insulating housing, terminals sealed to and closing off the ends of said housing and providing therewith a pressure tight enclosure, a relatively stationary contact mounted on one terminal and extending into said housing, a relatively movable contact in said housing for engaging and disengaging said relatively stationary contact and connected to the other terminal, a rod-lilre operator carrying said relatively movable contact at one end and at the other end extending through and slidably mounted relative to said other terminal, bellows means telescoped over said rod-like operator and secured in sealing engagement at one end thereto within said housing remote from said other terminal and at the other end to said other terminal, an arc extinguishing gas within said housing at a pressure above atmospheric pressure reacting against said bellows means in a direction to bias said rod-like operator and said relatively movable contact toward open position, nozzle means mounted on and movable with said relatively movable contact, and pump means also mounted on and movable with said relatively movable contact for causing a flow of said are extinguishing gas through said nozzle into the space between said contacts on separation thereof.

25. In a circuit interrupter, in combination, a cylindrical insulating housing, terminals sealed to and closing off the ends of said housing and providing therewith a pressure tight enclosure, main and auxiliary relatively stationary contacts mounted on one terminal and extending into said housing, relatively movable main and auxiliary contacts in said housing for engaging and disengaging said main and auxiliary relatively stationary contacts and connected to the other terminal, main and auxiliary rod-like operators carrying said main and auxiliary relatively movable contacts at one end respectively and at the other end extending through and slidably mounted relative to said other terminal, bellows means telescoped over each rod-like operator secured in sealing engagement at one end thereto within said housing remote from said other terminal and at the other end to said other terminal, and an arc extinguishing gas within said housing at a pressure above atmospheric pressure reacting against said bellows means in a direction to bias said rod-like operators and said main and auxiliary relatively movable contacts toward open position, nozzle means mounted on and movable with said relatively movable auxiliary contact, and pump means also mounted on and movable with said relatively movable auxiliary contact for causing a flow of said are extinguishing gas through said nozzle into the space between said auxiliary contacts on separation thereof.

26. In a circuit interrupter, in combination, a cylindrical insulating housing, terminals sealed to and closing ofi' the ends of said housing and providing therewith a pressure tight closure; a plurality of sets of series connected separable contacts in said housing interconnecting said terminals, each set including a relatively stationary contact and a relatively movable contact for engaging and disengaging the respective relatively stationary contact; means for conjointly moving said relatively movable contacts including a rod-like operator carrying one of said relatively movable contacts at one end and at the other end extending through and slidably mounted relative to said other terminal, bellows means telescoped over said rod-like operator and secured in sealing engagement at one end thereto within said housing remote from said other terminal and at the other end to said other terminal, an arc extinguishing gas within said housing at a pressure above atmospheric pressure reacting against said bellows means in a direction to bias said rod-like operator and said relatively movable contacts toward open position, nozzle means mounted on and movable with each relatively movable contact, and pump means also mounted on and movable with each relatively movable contact for causing a flow of said are extinguishing gas through each nozzle into the space between the respective set of separable contacts on separation thereof.

27. In a circuit interrupter, in combination, a cylindrical insulating housing, terminals sealed to and closing ofi the ends of said housing and providing therewith a pressure tight closure; a plurality of parallel connected sets of series connected separable main and auxiliary contacts in said housing interconnecting said terminals, each set including relatively stationary main and auxiliary contacts and relatively movable main and auxiliary contacts for engaging and disengaging the respective relatively stationary main and auxiliary contacts; means for conjointly moving said relatively movable main contacts including a rod-like operator carrying one of said relatively movable main contacts at one end and at the other end extending through and slidably mounted relative to said other terminal, means for conjointly moving said relatively movable auxiliary contacts including a rod-like operator carrying one of said relatively movable auxiliary contacts at one end and at the other end extending through and slidably mounted relative to said other terminal, bellows means telescoped over each rod-like operator and secured in sealing engagement at one end thereto within said housing remote from said other terminal and at the other end to said other terminal, an arc extinguishing gas within said housing at a pressure above atmospheric pressure reacting against said bellows means in a direction to bias said rod-like operators and said re1atively movable main and auxiliary contacts toward open position, nozzle means mounted on and movable with each relatively movable auxiliary contact, and pump means also mounted on and movable with each relatively movable auxiliary contact for causing a flow of said are extinguishing gas through each nozzle into the space between the respective set of separable auxiliary contacts on separation thereof.

28. In a circuit interrupter, in combination, a gas tight insulating housing having terminals at its ends, an arc extinguishing gas within said housing at a pressure above atmospheric pressure, parallel main and auxiliary separable contact means within said housing interconnecting said terminals and each having a travel of several inches between closed position and open position, main and auxiliary operators for opening and closing said main and auxiliary separable contact means respectively and extending externally of said housing and in fluid tight relation thereto, pump means in said housing movable with said auxiliary operator to cause said gas to flow only into the arc space formed on opening of said auxiliary separable contact means, main and auxiliary operating means connected externally of said housing to said main and auxiliary operators and arranged and adapted to open said main separable contact means and thereafter said auxiliary contact means, and means for applying kinetic energy incident to opening of said main separable contact means to said auxiliary operating means and thereby to said auxiliary separable contact means and to said pump means for operating the latter to aid in compressing said gas and causing it to flow into said are space.

29. The invention, as set forth in claim 28, wherein the main and auxiliary operating means comprise main and auxiliary operating arms, spring means bias said main operating arm and thereby the main operator and main separable contact means to open position, and means operatively interconnect said main operating arm to said auxiliary operating arm when the former has moved to a predetermined position to apply the kinetic energy to the auxiliary separable contact means and to the pump means.

30. The invention, as set forth in claim 29, wherein a disconnecting switch is connected in series with the parallel main and auxiliary separable contact means and is opened in timed relation to the operation thereof for disconnecting them from the circuit after it has been opened thereby to remove potential stress otherwise applied thereto.

31. Switch means comprising, in combination, a line contact member and a line terminal member in insulated spaced relation, a switch blade movable into and out of engagement with said line contact member, current interrupting means interconnecting said line terminal member and said switch blade, said current interrupting means comprising sequentially opening main and auxiliary contact means in parallel circuit relation each having a travel of several inches between closed position and open position, a gas tight insulating housingenclosing said main and auxiliary contact means, main and auxiliary operators for opening and closing said main and auxiliary separable contact means respectively and extending externally of said housing and in fluid tight relation thereto, pump means in said housing movable with said auxiliary operator to cause said gas to flow only into the arc space formed on opening of said auxiliary separable contact means, spring means biasing said operators for operating said contact means in turn to open position, latch means restraining said spring means, and operating means connected to said switch blade and to said operators for tripping said latch means to permit said spring means first to separate said main contact means followed by separation of said auxiliary contact means and operation of said 23 pump means thereby causing a flow of said gas into said are space, then moving said switch blade out of contact engagement with said line contact member, and finally reclosing said contacts and winding said spring means to be held by said latch means before said switch blade is reclosed.

32. The invention, as set forth in claim 31, wherein: (a) the latch means includes latch means individual to the main and auxiliary separable contact means, and (b) the operating means is arranged and adapted to release said latch means individual to said main separable contact means to initiate operation of the current interrupting means.

33. The invention, as set forth in claim 31 wherein means apply kinetic energy incident to opening of the main contact means to the auxiliary contact means and to the pump means for operating the same.

References Cited by the Examiner UNITED STATES PATENTS Berkey 200-144 Thornmen 200-145 Hoye 200146 Lingal et a1. 200-l48 Williams 200--146 Upton 200--146 Reece 200144 Baker 200148 Gussow et a1 200-145 FOREIGN PATENTS BERNARD A. GILHEANY, Primary Examiner. 

1. IN A CIRCUIT INTERRUPTER, IN COMBINATION, A CYLINDRICAL FRANGIBLE INSULATING HOUSING, HERMETIC SEALING MEANS CLOSING OFF EACH END OF SAID HOUSING, AN ARC EXTINGUISHING GAS WITHIN SAID HOUSING AT A PRESSURE ABOVE ATMOSPHERIC PRESSURE, A TERMINAL HAVING A BOTTOM PORTION SURROUNDED BY AN ANNULAR FLANGE TELESCOPED OVER EACH END OF SAID HOUSING, CEMENT SECURING EACH FLANGE TO THE RESPECTIVE END OF SAID HOUSING, SAID HERMETIC SEALING MEANS AT EACH END OF SAID HOUSING BEING INDEPENDENT OF THE ATTACHMENT BY CEMENT OF THE TERMINAL AND ANNULAR FLANGE TO THE RESPECTIVE END OF SAID HOUSING, SEPARABLE CONTACT MEANS WITHIN SAID HOUSING INTERCONNECTING SAID TERMINALS, AN OPERATOR FOR OPENING AND CLOSING SAID CONTACT MEANS EXTENDING OUT OF ONE END OF SAID HOUSING THROUGH THE HERMETIC SEALING MEANS THEREAT, SAID HERMETIC SEALING MEANS AT SAID ONE END INCLUDING A SEAL BETWEEN SAID OPERATOR AND THE HERMETIC SEALING MEANS THROUGH WHICH IT EXTENDS. 